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Abstract:

The present invention relates to a lid for closing a centrifuge rotor,
characterized by a form-fitting, rotation-actuated closure mechanism
which, pre-positioned on the centrifuge rotor, moves automatically into a
closed position by virtue of the intrinsic weight of the lid.

Claims:

1. A lid for closing a centrifuge rotor, wherein the lid comprises a
form-fitting, rotation-actuated closure mechanism, and wherein the
closure mechanism is capable of moving automatically into a closed
position when positioned on the centrifuge rotor by virtue of the
intrinsic weight of the lid.

2. The lid according to claim 1, wherein the closure mechanism is
rotationally actuated about a substantially vertical axis.

3. The lid according to claim 1, wherein the closure mechanism is a
thread.

4. The lid according to claim 3, wherein the closure mechanism is a
multi-turn thread.

5. The lid according to claim 1, wherein the closure mechanism comprises
a locking means for placing the lid into a completely closed position.

6. The lid according to claim 5, wherein the locking means is
form-fitting.

7. The lid according to claim 1, wherein the closure mechanism is a
bayonet.

8. The lid according to claim 1, wherein the closure mechanism is
arranged centrally on the lid.

9. The lid according to claim 1, wherein the closure mechanism has a
rotary knob.

10. The lid according to claim 1, wherein the closure mechanism is
capable of being actuated single-handedly.

11. The lid according to claim 1, wherein the closure mechanism is
designed to provide an acoustic indication that the lid is in the closed
position.

Description:

[0001] The present invention relates to a lid for closing a centrifuge
rotor.

[0002] Centrifuges are devices with which containers can be subjected to
centrifugal force. In the laboratory, for example, suspensions in test
tubes can be treated in this way in order to precipitate the floating
solid material at the bottom of the test tube. As a rule, centrifuges
have a rotary drive with a vertical drive shaft, on which a rotor can be
placed. Normally provided in the rotor are compartments, into which
containers which are to be centrifuged can be inserted. The rotors of the
centrifuge are often interchangeable, in order to centrifuge vessel
contents in one of the rotors while other rotors are only just being
loaded with containers, or can be ready for further processing together
with containers already centrifuged.

[0003] Since, for example, test tubes are pushed into the rotors so as to
be open at the top, operational reliability is served, inter alia, by
keeping the containers in a liquid-tight chamber during the centrifuging
in the rotor. On the other hand, this chamber should be accessible as
well as possible for the purpose of simple loading. Since, in particular
in the laboratory, a number of actions are often carried out at the same
time and the centrifuges nevertheless have to be closed carefully, it is
particularly advantageous to be able to use devices having as few actions
as possible, having as little actuating movement as possible and, if at
all possible, operationally reliably with only one hand. In this regard,
known centrifuges need improvement.

[0004] The present invention is based on the object of devising a lid for
closing a centrifuge rotor in which the handling is simplified.

[0005] According to the invention, this object is achieved by a lid having
the features of claim 1 or 11. Preferred refinements of the invention are
specified in the subclaims.

[0006] According to the invention, a lid for closing a centrifuge rotor is
characterized by a form-fitting rotation-actuated closure mechanism
which, pre-positioned on the centrifuge rotor, moves automatically into a
closed position by virtue of the intrinsic weight of the lid. As a
preferred refinement of the same or alternatively, a closure mechanism of
the lid according to the invention indicates the closed end position of
the lid on the centrifuge rotor acoustically, in particular by means of a
snapping or clicking noise.

[0007] For instance, a lid according to the invention can be rotationally
symmetrical about a substantially vertical axis--preferably the axis of
rotation of the rotor--and (similarly to a cooking pot lid having a
central knob) can have a central grip knob, with which the lid can be
placed on the rotor from above. Then, if the closure mechanism is for
example a movement thread having a sufficiently large slope angle then,
after being pre-positioned at the start of the thread, the lid can rotate
automatically into a closed position by virtue of the intrinsic weight of
the lid, guided in the thread. The closure mechanism preferably comprises
a locking means at the completely closed position of the lid--for example
at the end of the thread. In this way, therefore, given this
configuration according to the invention, it is sufficient to
pre-position the lid on the rotor from above with one hand on the grip
knob, then to release it, so that it itself rotates downward into a
virtually closed position and, finally, to turn it further by a few
degrees on the same grip knob, so that the lid locks in a closed position
in a then liquid-tight manner.

[0008] The locking means can be form-fitting, for example by the lid being
seated on its seals, which effect the tightness, before being locked and,
for example, counter to its resilient deformability, then coming to lie
with a form fit over a locking ledge with a pin in a locking undercut.

[0009] The locking mechanism provided can--to a certain extent in a way
similar in function to a thread--also be a bayonet, for example of the
type as is known and widespread for interchangeable objectives on reflex
cameras. In addition, the spring-prestressed locking means known from
there, also having an actuating lever for releasing the locking means,
can in principle be taken over directly for the lid according to the
invention.

[0010] These and other features of the invention and their possible
refinements will be described below with reference to the appended
drawings.

[0011] FIG. 1 shows a sectioned side view of a centrifuge rotor and a lid
therefor,

[0012] FIG. 2 shows a sectioned side view of the centrifuge rotor
according to FIG. 1 with the lid in the (virtually) closed position,

[0013] FIG. 3 shows a three-dimensional sectioned view of the centrifuge
rotor with lid according to FIG. 1, and

[0014] FIG. 4 shows a three-dimensional view of the closure mechanism of
the centrifuge rotor according to FIG. 1.

[0015] FIG. 1 reveals a centrifuge rotor 2, above which a lid 4 is
depicted, as is placed on the centrifuge rotor 2 by a hand (not
illustrated) of a user. The centrifuge rotor 2 has a row of holes or
compartments 6 distributed uniformly on the rotor periphery, into which
test tubes (not illustrated) can be plugged, oriented obliquely outward
at the bottom. Overall, the rotor is rotationally symmetrical about a
vertical axis 8 and, at the center, has a vertical central hole 9, by
means of which the rotor 2 can be plugged on to a centrifuge drive shaft
(not illustrated) for the centrifuging.

[0016] The compartments 6 for test tubes are accessible through a large
circular opening 10 in the top of the rotor 2. They are located on the
radial outer wall of a bowl-like chamber 11, which extends annularly
around a central hub 12.

[0017] Arranged in the bottom side of the hub 12 is the hole 9 for a
centrifuge rotor drive shaft. Toward the top, the hub 12 projects to a
certain extent circularly cylindrically out of the opening 10 and there
forms a substantial element of a closure mechanism 14 of the lid 4. To be
specific, the lid 4, which is circularly cylindrical in plan view, has in
the top side of its centre a grip knob 16 projecting circularly
cylindrically upward, which is hollow on the underside, therefore so to
speak has the form of a cup or hat. Gripped from above, for example, the
knob 16 with the lid 4 as a whole can be placed on the upper end 18 of
the hub 12 and thus pre-positioned. Without further rotational movement,
first of all the lid 4 falls vertically downward with the cup-like knob
16 along the vertical axis 8 on account of its intrinsic weight over the
upper end 18 of the hub 12, until three thread pins 20 which project
radially inward in the cup-like knob and which are distributed uniformly
on the periphery of the internal space 22 of the cup-like knob 16 come to
lie on the upper edge of the upper end 18 of the hub 12.

[0018] Pre-positioned in this way, because of its intrinsic weight, the
lid 4 slips further downward along the vertical axis 8 and, in the
process, is set rotating in the clockwise direction by a three-start
thread 24. The three-start thread 24 in the hub 12 can be seen
particularly well in the three-dimensional view of FIG. 4. Looking at
FIG. 4, the three-start thread 24 extends spirally downward on the
periphery of the hub 12 in the form of three spiral grooves 24. The
grooves 24 have such a width that the thread pins 20 can run in them,
guided in the interior of the cup-like knob 16 but without jamming. Thus
the lid 4 moves downward automatically by virtue of its intrinsic weight,
rotating about the vertical axis 8, until its O-ring seal 26 (on the
underside on the outermost rim of the lid) comes to lie on the upper edge
of the rotor opening 10. This position of the lid 4 on the rotor 2 can be
seen in FIG. 2.

[0019] Only in this position is it necessary for the user to grip the knob
16 once more (on the top of the lid) for the final liquid-tight closure
of the lid 4 on the rotor 2 and to rotate it by a few degrees in order to
lock the lid 4 on the rotor 2. Then, again looking at FIG. 4, it can be
seen that, as the closure mechanism, the grooves 24 of the three-start
thread have at their lower end a locking position 27 for the thread pin
20 behind a ledge 28. By means of active further rotation of the lid 4,
guided by its thread pins 20 in the thread turns 24, the thread pins 20
then overcome the ledges or "humps" 20 counter to the prestress of the
resilient seal 26, which is pressed in a liquid-tight manner into a
sealing groove 30 on the outer rim of the rotor opening 10. Behind the
humps 28, the thread pins 20 are then located and locked with a form fit
in the locking positions 27 at the end of the thread turns 24.

Patent applications in class WITH MEANS FOR INDICATING, INSPECTING, MEASURING, SIGNALING OR TESTING

Patent applications in all subclasses WITH MEANS FOR INDICATING, INSPECTING, MEASURING, SIGNALING OR TESTING